FE-FC Holden Discussion Forum

I have roller rockers YT5007 to fit on 179 head.

I have only fitted standard rockers before.

I assume:

• The roller end of the rocker sits on the valve stem
  
• The recessed or "countersunk" side of the rocker faces upwards where it sits on the stud - this would be so the tensioning nut seats nicely
  
• The smaller allen key head scew goes into the main nut once the rockers are adjusted properly - it gets tightened down so that the nut is locked in place

If someone could confirm these assumptions that would be great.

Also, most workshop books dicate 1/4 - 3/4 turn past chatter. Does anyone have a preference for which end of this scale is best to stick to?

just wondering first, have you got guide plates?

yes the roller tip is on the valve .. yes counter sunk side up .. yes little allen key is your lock nut.. are you running solid or hydraulic lifters?? hope this helps

Thankyou,

I am running hydraulic lifters.

Leon, no I don't think I have guideplates - aren't they only for 202 heads?

Cheers
Dave

if you buy guide plates try to get some that fit a six, mine are yt and are not very good as they need to be modified to fit a six.

I haven't long got my old girl going with the yt roller rockers on a early head and I've been assured I don't need guide plates. I went half turn past zero tolerance with hydraulic lifters and it seems fine. The big, big problem I have is trying to stop the buggers hitting the rocker cover sides. I have the high clearance chrome job for roller rockers and they still bounced of the sides at about 3500 revs. I have since modified it out of desperation with a big hammer so it looks yuck and I even split the rear of the cover and braised it up to allow clearance to the rear rocker and I still have a problem somewhere. I don't know if it is the type of rockers I've used or a common problem with YT's.
The rear rocker (No 6 Exhaust) seems to be the main offender.
Any one else with suggestions or experience on this?
Addo

Hi Addo,

I'm running Erson rollers with solid cam/lifters without guide plates. I'm also running a stock rocker cover without rocker fouling and have revved over 7000 rpm. No problems.

When I bought my XU1 it had a 161 motor fitted with YT rockers under a tall aftermarket cover, no fouling, no guides, again - no problems.

Not sure why you would be getting issues, especially with the higher cover??

Hope this helps somehow!!

Cheers,

Craig.

used crane rockers off a holden v8 had the same problem with them slapping the side so i found an early cast alluminium one the tallest i could find ran sweet holden red motor shouldnt need guide plates and your right addo half a turn on should be spot on cheers Andy

Addo, my 202 has a set of Yella Terra (Street Terra?) roller rockers and they fouled the old alloy Thomas rocker cover. I had to relieve the inside a fair bit for clearance, but I never had any issues with the normal chrome cover. HTH.

Hi Guys.

On the guide plate thing. These are only needed for 173 and 202 engines. The 149, 161, 179 & 186 heads use the holes where the pushrods go thru, to act as guides. These holes in the 173/202 are larger & round & won't act as guides.

Dr Terry

Next time I have another go at getting clearance on the rockers, (over Xmas) I'll check the part no and find out just what they are and/or off and see if that sheds some light. They came already set up on the head I used that came off the racing 202 I previously posted.
Funny thing is I used the rocker cover off the same motor but I guess with all the racket with very little exhaust plus solids they may have always been hitting without any one realizing.
Addo